The general-purpose digital computer is one of the most powerful and remarkable information processing tools ever invented. Indeed, the advent of the digital computer has thrust the world headlong into what is now recognized by many analysts as an "information era" and an "information economy," in which the ability to access and process information in an effective manner is one of the most important forms of economic power.
The potential impact of the digital computer on information processing is undeniably revolutionary. Yet, conventional software environments are generally organized around metaphors and principles from earlier eras. Text-based operating systems like Microsoft DOS essentially treat the computer as a giant filing cabinet containing documents and applications. A strictly hierarchical file directory provides a rigid, tree-like structure for this digital file cabinet. Individual documents are the "leaves" of this tree hierarchy. The directory structure generally does not include or express relationships between leaves, and users generally access documents and applications individually, using the directory structure. Even the now ubiquitous graphical "desktop" computing environment, popularized for personal computers by the Apple Macintosh.RTM. and Microsoft Windows.RTM. operating systems, also simulates a traditional office environment. Individual documents and applications, represented by graphical icons, are displayed on the user's screen, to be accessed one-at-a-time. Once again, a strictly hierarchical, tree-like directory structure is imposed to organize the contents of the desktop.
Although the desktop and file cabinet metaphors have been commercially successful, the limitations and drawbacks of these traditional metaphors become clear when one considers the strikingly different way in which the world's other powerful information processing machine--the human brain--organizes information. Instead of being confined and limited to strictly hierarchical file directory structures, the human brain is thought to interconnect numerous pieces of information through flexible, non-hierarchical, associative networks. As those of skill and experience in the art are aware, it is often clumsy for users of traditional, prior art operating system interfaces to process multiple pieces of information if these pieces are contextually related in some way, but are stored in separate files and/or are associated with different application programs. These traditional limitations therefore often lead frustrated users to organize their thought processes around their computer software, instead of the reverse.
What is desired is an effective methodology for organizing and processing pieces of interrelated information (or "thoughts") using a digital computer. The methodology should support flexible, associative networks of digital thoughts, and not be limited to strict, tree hierarchies as are conventional, prior art technologies. A related goal is to create an intuitive and accessible scheme for graphically representing networks of thoughts, providing users with access to diverse types of information in a manner that maximizes access speed but minimizes navigational confusion.